Richmond Leader

People infected with the COVID-19 omicron variant are significantly less likely to develop smell and taste loss compared to those infected by delta and earlier COVID-19 variants, according to results published this month by Virginia Commonwealth University researchers in the journal Otolaryngology — Head and Neck Surgery.

Researchers used a national database of over 3.5 million cases of patients who tested positive for COVID-19 since the onset of the pandemic. Compared to rates of smell and taste loss during the early phase of the pandemic in 2020 before variants were identified, chances of smell and taste loss were just 17% for omicron, 44% for delta and 50% for the alpha variant.

“As the pandemic continues and new variants emerge, this is very good news for patients,” said Daniel Coelho, M.D., lead author and a professor in the Department of Otolaryngology — Head and Neck Surgery at the VCU School of Medicine. “We now know that each variant has a different risk factor for associated smell and taste loss and have reason to believe that newer variants are less likely to impact smell and taste.”

The findings have a huge diagnostic impact, said Coelho, an ear, nose and throat specialist at Children’s Hospital of Richmond at VCU.

“Loss of smell and taste is still a good indicator of a COVID-19 infection, but the reverse is no longer true,” Coelho said. “Do not think you are COVID-negative just because your sense of smell and taste is normal.”

Coelho was one of the authors, along with Evan Reiter, M.D., medical director of VCU Health’s Smell and Taste Disorders Center and professor of otolaryngology; Richard Costanzo, Ph.D., the center’s research director and professor emeritus in the Department of Physiology and Biophysics; and Evan French, research informatics systems analyst at VCU’s C. Kenneth and Dianne Wright Center for Clinical and Translational Research.

The paper, “Decreasing Incidence of Chemosensory Changes by COVID-19 Variant,” is based on data provided by the National COVID Cohort Collaborative, a database sponsored by the National Institutes of Health with over 3.5 million patient cases. Coelho and his team identified 6-week periods where cases were highest for each variant studied, then compared how many patients were diagnosed with smell and taste loss in these timeframes.

The latest findings could offer a clue in figuring out what part of the molecular structure of the COVID-19 virus causes the olfactory decline.

“Unlocking what causes smell and taste loss in the first place will help us better determine how to treat it,” Coelho said.

Next, the research team will study the recovery time from smell and taste loss based on the different variants. More research is needed to explore if vaccination status also plays a role in the reduced rates of smell loss.

Since April 2020 when news reports of smell and taste loss as a symptom of COVID-19 became widespread, researchers at VCU have been working to determine how long COVID-19-related smell or taste loss might last to help identify treatments or other considerations for the health of those who’ve lost these senses. Over 3,000 people across the U.S. participated in the survey, which tracked symptoms over time.

Coelho and Costanzo are also leading a team to develop an implant device to restore sense of smell, much like a cochlear implant restores hearing for those with hearing loss. The project, which they have been working on for several years, has received international interest since the onset of the pandemic as more cases of smell loss arise.

“This is not just about being able to enjoy a fine bottle of wine again; it’s about safety and preserving your quality of life,” Coelho said. “Our research shows that more than 50% of people suffering from smell and taste loss have reported feeling depressed. Patients with smell loss also have a higher rate of dementia. Fewer people experiencing these symptoms means fewer people being impacted by mood changes and cognitive problems.”

This study received grant funding from the MEDARVA Foundation. The Wright Center, which oversees clinical research at VCU, established the database for the survey of those experiencing loss of smell and taste through funding from a National Institutes of Health grant and supports the National COVID Cohort Collaborative as a Clinical and Translational Sciences Awards Program hub.

Original source can be found here.